Thuja plant named ‘RutThu5’

ABSTRACT

A new and distinct cultivar of  Thuja  plant named ‘RutThu5’, characterized by its nice, columnar form, dark green foliage that does not have chartreuse tips like  Thuja occidentalis  ‘Emerald Green’. ‘RutThu5’ can be grown with one cutting per pot compared to the industry standard of three cuttings per pot, and has similar growth rate in containers and field as three-cutting plants of ‘Emerald Green’. The new ‘RutThu5’ has demonstrated cold hardiness to about −34° F. in trials conducted in Minnesota.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. provisional application titled“Thuja PLANTS NAMED ‘RutThu2’, ‘RutThu3’, ‘RutThu4’, and ‘RutThu5’”having Ser. No. 63/217,004, filed on Jun. 30, 2021, which is entirelyincorporated herein by reference.

Botanical designation: Thuja occidentalis.

Cultivar denomination ‘RutThu5’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Thuja,botanically know as Thuja occidentalis, and hereinafter referred to bythe cultivar name ‘RutThu5’.

The new Thuja cultivar ‘RutThu5’ is a product of open pollination ofThuja occidentalis ‘Fastigiate’ (unpatented). The open-pollinated seedswere obtained in 2011 from Estonia. Seedlings were planted inWatkinsville in 2014. The new cultivar ‘RutThu5’ was selected for itsupright, oval, columnar growth form, darker green color than Thujaoccidentalis ‘Emerald Green’, one cutting per pot growth with similargrowth rate to three-cutting plants, and cold hardiness to about −34° F.in trials conducted in Minnesota.

Asexual reproduction of the new Thuja ‘RutThu5’ using hardwood cuttingshas been continued in Watkinsville, Ga. since 2015. Observations of theresulting progeny have shown that the unique features of this new Thuja‘RutThu5’ are stable and reproduced true to type in successivegenerations. The new ‘RutThu5’ has also been grown in MN.

SUMMARY OF THE INVENTION

The new Thuja cultivar ‘RutThu5’ has not been observed under allpossible environmental conditions. The phenotypes may vary somewhat withvariations in environment and cultural practices such as temperature,water and fertility levels, soil types, and light intensity without,however, any variance in genotype.

The following traits have been repeatedly observed and are determined tobe the unique and distinguishing characteristics of the new Thujacultivar named ‘RutThu5’. In combination, these traits set ‘RutThu5’apart from all other existing varieties of Thuja known to the inventors.

-   -   1. upright, oval, columnar growth form;    -   2. darker green color than Thuja occidentalis ‘Emerald Green’        and new growth that does not have chartreuse color of new growth        of ‘Emerald Green’;    -   3. ability to be grown with one cutting per pot, compared to        industry standard of three-cuttings per pot for cultivars like        ‘Emerald Green’;    -   4. similar growth rate for one-cutting plants in the field and        containers as compared to three-cutting plants of ‘Emerald        Green’;    -   5. cold hardiness to about −34° F. in trials conducted in        Minnesota.

Plants of the ‘RutThu5’ can be compared to similar cultivar Thujaoccidentalis ‘Emerald Green’ (unpatetend) and differs from ‘EmeraldGreen’ in that ‘RutThu5’ has a more columnar form than ‘Emerald Green’,which is more conical. The foliage of ‘RutThu5’ is also darker green anddoes not have the chartreuse new growth of ‘Emerald Green’. ‘EmeraldGreen’ is grown from three cuttings, but the new ‘RutThu5’ can be grownfrom one cutting per pot, but the one cutting plants have a similargrowth rate in the field and containers as the three-cutting plants of‘Emerald Green’. Male parent plant is not conclusively known, socomparison data is not available. The new Thuja ‘RutThu5’ can also becompared to female parent Thuja occidentalis ‘Fastigiate’ (femaleparent) in that height to width ratio of ‘RutThu5’ is 2.1 compared toapproximately 6.0 for ‘Fastigiate’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying, colored photographic illustrations show the overallappearance and distinct characteristics of the new cultivar Thuja‘RutThu5’ showing the colors as true as possible. Colors in thephotographs may differ slightly from the color values cited in thedetailed botanical description. The photographs were taken around June,2021 of plants grown outdoors in Watkinsville, Ga.

The photograph labeled FIG. 1 depicts a side view of a typical7-year-old ‘RutThu5’ plant showing the upright, columnar form andfeatures.

The photograph labeled FIG. 2 depicts a close-up view of the branchesand needles of a typical 7-year-old ‘RutThu5’ plant showing the darkgreen color and lack of chartreuse-coloring on new growth.

DETAILED BOTANICAL DESCRIPTION

The following traits have been consistently observed in the originalplants of the new varieties and in asexually propagated progeny grown inWatkinsville, Ga., (and some in MN) and, to the best knowledge of theinventors, their combination forms the unique characteristics of the newvariety ‘RutThu5’.

Throughout this specification, color names beginning with a small lettersignify that the name of that color, as used in common speech, is aptlydescriptive. Color names beginning with a capital letter designatevalues based upon The R.H.S. Colour Chart, 5^(th) edition published byThe Royal Horticultural Society, London, England in 2007, except wheregeneral terms of ordinary dictionary significance are used.

The aforementioned photographs and following observations, measurements,and values describe plants of the Thuja cultivar named ‘RutThu5’. Datawere collected from a horticulture farm in Watkinsville, Ga. from6-year-old plants. The average low temperatures ranged from about 20° F.to 30° F. in the winter and about 90° F. to 100° F. in summer.

-   Botanical classification: Thuja ‘RutThu5’.-   Commercial classification: Ornamental conifer.-   Parentage: Open pollination of Thuja occidentalis ‘Fastigiate’ by    unknown pollen parents.-   Growth and propagation:    -   -   Propagation type.—Terminal or sub-terminal hardwood            cuttings.        -   Growth rate.—Moderate to fast.        -   Root description.—Typically about 2-6 roots arising from the            base of the cuttings.        -   Rooting habit.—Good.-   Plant description:    -   -   Habit.—Of 6-year-old plant in field — upright oval,            columnar.        -   Usage.—Various uses, including landscaping, ornamental,            container, border, hedge, and mass planting.        -   Vigor.—Good.        -   Size of 4-year-old plant.—A. Height: From soil level to top            of plant, about 64 inches (about 114 inches for 6-year-old            plant). B. Width: About 28 inches (about 54 inches for            6-year-old-plant). C. Ratio: About 2.3.        -   Branch/stem (terminal tuft).—A. Quantity: Numerous. B.            Length: About 6-13 cm. C. Base Diameter (year 2): About 4-5            mm at 15 cm from tip. D. Branch angle: About variable from 0            to about 65° from center. E: Odor (of bruised stem): Mild            evergreen scent. F. Internode length: About 12-25 mm (about            5 internodes per sample). G: Color (R.H.S.): (At ½ year)            Yellow Green 154B to Greyed-orange 177B. H: Strength of            lateral branches: Good. I: Pubescence: None. J: Shape:            Round. K: Bark texture smooth, semi-gloss. L: Bark color:            Grey Brown 199B.        -   Leaf.—A. Leaf type: Scale. B. Mature size (L×W): About 2.5            mm×about 3 mm. C. Arrangement on stem: Decussate. D. Aspect:            Upright to slightly spreading. E. Color (R.H.S.): Upper —            Green 137A; Lower — Green 139C. F. Leaf Number: Average of            about 8-10 per cm/stem. G. Apex: Acute-acuminate. H. Base:            Rounded. I. Margin: Smooth/Hyaline. J. Shape: Flattened,            decussate no lobes present. K. Pubescence: None. L.            Venation: None. M. Texture: Waxy, abaxial gland present. O.            Odor when crushed: Mild evergreen. P. Winter Discoloration:            Greyed-Orange 165B.        -   Long shoots.—A. Facial Gland: Present. B. Leaf Shape:            Linear. C. Color: Greyed-orange 177B. D. Tips:            Free/acuminate. E. Apex: Acute.        -   Coning production.—None.        -   Seed.—None.-   Weather/temperature tolerance: Plants of the new Thuja have been    observed to grow in USDA Zone 8a, with heat tolerance, and have a    USDA Zone range 3-8. ‘RutThu5’ has also been cold hardy to about    −34° F. in trials conducted in Minnesota.-   Disease/pest resistance: To date, plants of the new Thuja have not    been observed to have any diseases or pests in USDA Zone 8a when    grown under standard conditions. Specifically, a common fungus,    Passalora sp., identified on other conifers in USDA Zones 6-8, has    not been observed on plants of the new Thuja ‘RutThu5’.

It is claimed:
 1. A new and distinct cultivar of the Thuja plant named‘RutThu5’ as illustrated and described herein.